Basics Of Network Layer Part - 2

Duration: 18 min

This video lesson is available to enrolled students.

Return to /learn/SSC-JE-IMD-SCIENTIFIC-ASSISTANT-COMPUTER-SCIENCE/computer-networks/net-layer-ipv4-proto/net-layer-ipv4-basics/asset-basics-of-network-layer-part-2 after enrolling

Inside: a video lesson and guided study material.

Module outline

  1. General Intelligence & Reasoning: Analogy, Non Verbal Reasoning (Spatial Aptitude) (Spatial Reasoning) (Visual Reasoning), Series (Number and Letter Series) (Numerical Relations and Reasoning), Coding Decoding, Blood Relations, Directions (Direction Test), Ranking, Order and Sequence, Logical Sequence Of Words, Syllogisms, Venn Diagram, Deductive and Inductive Reasoning (Logical Deduction and Induction) (Prepositional Reasoning), Selection Decision Table (Decision Making), Data Sufficiency, Puzzle Solving (Puzzles), Data Arrangement, Cubes & Dices, Calendar, Clock, Arithmetic, Number System, HCF LCM, Verbal Analogy (Word Based Analogy), Visual Recognition and Figure Completion, Paper Folding and Cutting, Transformation of Shapes, Clocks and Calendars, Direction Sense, Cubes and Dice, Patterns in Two-Dimensional Figures, Seating Arrangements, Analogy and Classification, Logical Deduction and Induction, Alphabet and Word Tests, Mathematical Operations, Series Completion, Simplification and Approximation, Coding and Decoding, Numerical Reasoning, Assembling and Grouping of Shapes, Three-Dimensional Patterns and Visualization, Vocabulary, Number System, Averages, Mixtures and Alligation, Simple and Compound Interest, Percentages, Algebra, Speed, Time and Distance, Seating and Arrangement Puzzles, Traverse Surveying, Order, Ranking and Sequence, Constraint Puzzles, Syllogisms and Venn Diagrams, Reading Comprehension, Critical Reasoning, Permutations and Combinations, Narrative Sequencing, Project Monitoring, Resources and Safety, Profit, Loss and Discount, Ratio and Proportion, Time and Work, Mensuration, Data Interpretation, Powers, Surds and Logarithms, Sequences and Series, Articles and Determiners, Sentence Completion, Data Sufficiency, Blood Relations, Simple Interest and Compound Interest, Mixture and Alligation, Sequence and Series (Series), Speed Time and Distance, Algebra, Profit and Loss, Powers and Exponents (Surds and Indices), Permutation and Combination
  2. General Awareness: Physics, Chemistry, Biology, History, Geography, Polity, Indian Economy, Environment, Static General Knowledge, GK- Current Affairs, Artificial Intelligence, MS Office Applications, Terms & Abbreviations, Keyboard Shortcuts, Evolution of Indian Banking (Banking & Financial Awareness), Emerging Tech Trends
  3. Engineering Mathematics: Set Theory, Relations, Functions, Graph Theory, Group Theory, Propositional and Predicate Logic, Linear Algebra, Calculus, Probability, Statistics, Signal Space and Optimum Detection, Probability, Statistics
  4. Digital Logic: Digital Systems & Boolean Basics, Logic Gates & Hardware, Boolean Expression, Boolean Minimization, Combinational Circuit, Sequential Circuits, Number System, Number Representation, Floating Point Rep, Number Systems and Codes, Registers and Counters, Boolean Algebra and Logic Gates, Microprocessors and Microcontrollers, Logic Families and CMOS Logic, Microprocessors, Logic Gates and Boolean Algebra, Minimization of Boolean Functions, Timing, Hazards and Testing, Logic Families, Combinational Logic Design, Arithmetic Circuits, Waveform Generators and Timer Circuits, Semiconductor Memories and Programmable Logic Devices, Combinational Logic Circuits, Latches and Flip-Flops, Finite State Machines, Sequential Circuits and State Machines, Minimization of Boolean Functions, Arithmetic Circuits, Latches and Flip-Flops, Number Systems and Codes, Registers and Counters
  5. Computer Organisation & Architecture: Basics of COA, Cache Memory Organization, Input Output Organisation, Pipelining, Instr Formats & Modes, Control Unit Design, Programming the Basic Computer, Register Transfer and Microoperations, Semiconductor Memories and Programmable Logic, Processor Organization and Instructions, Memory Hierarchy and Input/Output, Registers and Counters
  6. Programming & Data Structures: C Fundamentals, Control Flow, Functions, Arrays & Pointers, Storage Classes, Structures & Enums, DMA, Macros, Scoping & File Handling, Introduction to DS, Array, Stack, Queue, Linked List, Tree, Graphs, Hashing, HTML Basics, OOPS with C++, Java, Object Oriented Technology
  7. Databases: Basics of DBMS, ER Diagram, Relational Model & Functional Dependencies, Keys & Integrity Constraints, Normalization (1NF - BCNF), Decomposition Properties & 4NF, File Organization & Indexing, Relational Algebra, SQL, Relational Calculus, Transaction Management, Concurrency Control, Database Recovery, Database Security & Authorization
  8. Algorithms: Algorithm Analysis, Time Complexity Analysis, Sorting Algorithms, Greedy Algorithms, Dynamic Programming, Minimum Spanning Trees, Shortest Path Algos
  9. Theory of Computation: Introduction to TOC, Deterministic FA (DFA), Non-Deterministic FA, Regular Expressions, Grammar, Regular Language Properties, Moore & Mealy Machines, Pushdown Automata & CFG, Turing Machines, Complexity Theory
  10. Compiler Design: Intro to Compilers, Lexical Analysis, Grammar & CFG, Syntax Analysis: Top-Down, Syntax Analysis: Bottom-Up, Semantic Analysis & SDT, Intermediate Code Gen, Code Optimization, Run Time Environment
  11. Operating System: Introduction to OS, Process Management, CPU Scheduling, Process Synchronization, Threads & Process Creation, Deadlock, Memory Management, Virtual Memory, Disc Scheduling, File Management, Security, Windows OS, Distributed Systems, Unix OS, Linux OS
  12. Computer Networks: Introduction to CN, DLL: Access Control, DLL: Flow Control, DLL: Error Control, DLL: Framing, Data Link Layer - Ethernet, Net Layer: IPv4 & Proto, Net Layer: IP Addressing, Net Layer:Routing Protocol, Transport Layer Services, TL: Congestion & UDP, Application Layer, Hardware Basics, Data Communication, Website, Browser & Services, Web Design & Development, Network Security, Cyber Threats and Malware Attacks, Cyber Safety and Security
  13. Full Length Mock Tests:
  14. Sectional Tests:
  15. Paper 2 - Full-length Mock Tests:
AI summary & chapters

AI Summary

An AI-generated summary of this video lecture.

This lecture, titled 'Basics Of Network Layer Part - 2', systematically covers the core functions and services of the network layer in computer networking. The instructor begins by defining packetizing, emphasizing that it involves encapsulating the payload received from the upper layer into a network-layer packet at the source and decapsulating it at the destination. A vertical protocol stack diagram (TL, NL, DL) is drawn to illustrate how a header containing source and destination addresses is added. The lecture then details that the network layer does not directly provide error control or flow control; instead, it relies on a checksum in the datagram header and the ICMP protocol for limited error detection. Congestion control is defined as a state where too many datagrams exist in an area of the network. The core responsibility of the network layer is identified as source-to-destination delivery across multiple networks, illustrated with a diagram of two connected network clouds. The lecture concludes by introducing logical addressing as the mechanism required to distinguish sender and receiver systems when packets cross network boundaries, and defines routing as the process of finding the best route in an internetwork created by connecting independent networks.

Chapters

  1. 0:00 – 2:00 00:00-02:00

    The instructor introduces packetizing, defined on-screen as 'Encapsulating the payload (data received from upper layer) in a network-layer packet at the source and decapsulating...'. A red underline highlights 'source' in the first bullet. The instructor draws a vertical stack of layers labeled 'TL', 'NL', and 'DL' on the board, using arrows to show flow between the network and data-link layers. This visualizes how a header containing source and destination addresses is added to the payload.

  2. 2:00 – 5:00 02:00-05:00

    The lecture transitions to error control and flow control. The slide states 'Error Control: Error control is not directly provided in the Network layer, but checksum is added in datagram to...'. The instructor explains that routers are not allowed to decapsulate packets unless fragmentation is required. A protocol stack diagram showing IP, ICMP, and ARP is displayed. The instructor then defines flow control, noting the network layer does not directly provide it because its job at the receiver is simple and rarely overwhelmed.

  3. 5:00 – 10:00 05:00-10:00

    The instructor defines congestion control as a situation where 'too many datagrams are present in an area of the network'. The core responsibility of the network layer is then introduced: 'source-to-destination delivery of a packet'. A hand-drawn diagram shows two distinct network clouds (A and B) connected by a link, with source (S) and destination (D) nodes labeled to illustrate multi-network delivery. The slide transitions to 'NETWORK-LAYER SERVICES', highlighting 'Logical addressing' as the mechanism needed when a packet passes a network boundary.

  4. 10:00 – 15:00 10:00-15:00

    The lecture focuses on routing and packetizing. The slide defines 'Routing: When independent networks or links are connected to create internetworks'. The instructor explains that one of the network layer's functions is to provide this mechanism, noting 'There is more than one route from the source to the destination'. A diagram illustrating network connections and routes is drawn. The instructor then transitions back to packetizing, drawing a rectangle divided into an 'H' header box and an oval payload marked 'P', with an arrow labeled 'T'.

  5. 15:00 – 17:39 15:00-17:39

    The lecture revisits the opening slide's first bullet on packetizing and encapsulation. A later slide lists bullets for 'Error Control', 'Flow Control', and 'Congestion Control', stating ICMP provides some level of error control. A protocol stack diagram on the right shows Application, Transport (SCTP, TCP, UDP), Network (IGMP, ICMP, IP, ARP), Data-link, and Physical layers. The instructor reinforces the distinction between direct network layer functions and those handled by upper or lower layers.

The lecture progresses from basic encapsulation to complex internetworking concepts. It starts with packetizing, using a vertical protocol stack (TL, NL, DL) to show header addition. It then clarifies what the network layer does NOT do directly (error/flow control), relying instead on checksums and ICMP. The core function—source-to-destination delivery across multiple networks—is illustrated with a two-cloud diagram. Logical addressing is introduced as the solution for distinguishing systems across network boundaries, and routing is defined as finding the best path in an internetwork. The hand-drawn diagrams (layer stacks, network clouds, header/payload boxes) are central to visualizing these abstract concepts. Key terms like 'source-to-destination', 'Logical addressing', and 'Routing' are repeatedly emphasized on slides.

Loading lesson…